1. Field of the Invention
The present invention relates to a process for obtaining on a support a cast shadow faithfully reproducing a mask pierced with fine periodically distributed parallel slits, in which the mask is illuminated with a flat monochromatic wave which is polarized perpendicularly to its plane of incidence so that the electric field vector is parallel to the slits.
2. Description of the Prior Art
Presently, it is very difficult to provide a faithful reproduction of a mask pierced with very fine slits on a mask. When a mask of this type is illuminated, there occur in fact numerous parasite diffractions which prevent reproduction on the support of a cast shadow which corresponds faithfully to the mask and which has perfectly contrasted contours.